Improvement in cylindrical steam-valves



NITED STATES PATENTA OFFICE.

WILLIAM H. AKINS, OF DRYDEN, AN. Y.

IMPROVEMENT IN C YLINDRICAL vSTEAM-VALVES.

Specification forming part of Letters Patent No. 43,824, dated August 16, 1864.

' same, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure l represents a horizontal section of a steam-cylinder provided with my improved V..lves. Fig. 2 is a side elevation ofthe same.

Similar letters of reference indicate like parts.

This invention consists in a solid plug' provided with a cavity and fitted in a case surrounded by an annular steam-chamber furnished with three or more ports and divided ot'in three or more separate compartments, one to communicate with the interior of the cylinder, and one with the steam and the other with the exhaust pipe in such a manner that the plug is relieved from all, or nearly all, pressure ot' steam, and therefore can be moved instantaneously, andby turning said plug over a small arc the interior of the cylinder can be brought to communicate either with the steam or with exhaust pipe, as circumstances will require.

Arepresents a steamcylinder, constructed, in the ordinary manner, of iron or any other suitable material, and provided with a piston, B, as clearly shown in Fig. l ot' thcdra-wings. This cylinder receives steam and exhausts through the channels a a. at or near its ends, and these channels communicate through the valve-chambers and valves with the steampipe G, and with the exhaustpipe H. The valves E E consist of plugs provided with cavities e e, and they are itted nicely into ctses F F, each of which is provided with three ports, ff* f* *ff/*ff* it, and which are surrounded by annular steam-chambers g g. Each of these steam-chambers is divided oft in three compartments by partitions h h', two of which serve to separate the port f* from the ports f and f* 'it and the port j" t from the ports f and j" it it, While the third partition in each steam-chamber is situated between the ports f f t t f j" 't i, respectively. The compartments thus formed in each ofthe annular steam-chambers communicate, one with the interior ofthe cylinder, one with the steam-pipe, and one with the exhaust-pipe H.

lf the valves are in the position shown in Fig. l of the drawings, the steam enters from the pipe G through the port f, cavity e, port fit, and channel a into the cylinder, imparting to the piston motion in the direction of the arrow marked thereonin the drawings, at'

the same time the steam from that portion of the cylinder infront of the piston exhausts through the channel a port f it, cavity e', port fit it, and exhaust-pipe H.

Instead of .using two valves, one at each end of the cylinder, one valve might be used in the middle, and in that case the plug would have to be made with two cavities, one oppoposite the other, and the ca se surrounding the plug would have to be made with six ports instead of three. Butif two valves are used, as shown in the drawings, they will be connected by a rod, T, so that they will be changed simultaneously by the action of suitable lugs projecting from a disk and acting on a tapprt secured in the rod, or by any other suitable mechanism.

A valve constructed according to my invention is exposed to a very slight pressure, the only portion exposed to the same being thel area of the cavities e e', and for this reason my valves move with very little power, and can be changed instantaneously. By this arrangement I am enabled to overcome the dead-centers in a reciprocating engine, and to operate the same with great economy in steam compared with the power derived from the same.

Having thus described my invention, I claim as new and desire to secure by Letters Patent-- The solid plug or plugs E E', provided with cavities e e', and fitted in cases F F', with portsfftf* *f/,f *f 'it it, to operate in combinatiou with the annular steam-chambers g gf, each divided offin three compartments, to communicate with the interior of the cylinder, with thestcam pipe, and with the exhaustpipe, in the manner and for the purpose substantially as herein shown and described.

W. II. AKINS-` Witnesses:

WM. F. MCNAMARA, J. P. HALL. 

